Water-tight shutter construction for observatory domes



Aug. 22, 1961 J. o. PAULSON 2,996,844

WATER-TIGHT SHUTTER CONSTRUCTION FOR OBSERVATORY DOMES Filed Jan. 28, 1959 5 Sheets-Sheet 1 R1 INVENTOR 5 ehhndPawlson 8 j BY 5 ATTORNEYS Aug. 22, 1961 J. o. PAULSON 2,996,844

WATER-TIGHT SHUTTER CONSTRUCTION FOR OBSERVATORY DOMES Filed Jan. 28, 1959 3 Sheets-Sheet 5 INYENTOR John 0. Paulson BY yaw! ATTORNEYS United. States Patent 2,996,844 WATER-TIGHT SHUTTER CONSTRUCTION FOR OBSERVATORY DOMES John O. Paulson, Canton, Ohio, assignor to Astro-Dome, Inc., Canton, Ohio, a corporation of Ohio Filed Jan. 28, 1959, Ser. No. 789,592 2 Claims. (Cl. 50-51) The invention relates to shutters for observatory domes and more particularly to a water-tight construction whereby when the shutters are closed the interior of the dome will be completely water-tight.

Observatory domes for astronomical purposes and the like are usually provided with a pair of oppositely slid.- ing shutters for closing the opening in the dome through ice I dome and being straight in cross section. Similarly curved frame members are fixed upon the dome in spaced relation and frame the opening through which a telescope orsimilar instrument may be sighted, which opentelescope is not in use.

. the telescope within the dome, and for slidably moving which a telescope or similar instrument may be sighted,

when the telescope is not in use;

It is important that the telescope and other costly equipment usually housed within such domes be properl y protected from the entrance of moisture into the dome.

In such domes as are now in general use, diificulty has been experiencedby water entering the interior of the dome at the point where the shutters are located, due to the fact that under present practice the shuttersdo not provide a completely water-tight closure when they are in the normal closed position. This may cause considerable damage'to the instruments within the dome. The present invention contemplates a construction of shutters for 'observatory domes which provides a completely water-tight closure when the shutters are in the closed position to which they are moved when the .-i

telescope is not in use.

Another object of the invention is to provide a shutter construction for observatory domes; in which the shut:- ters are provided at their meeting edges with a plurality of bafiles and drain troughs providing a tortuous path through which water entering the joint between the shutters will be conducted and drained on the exterior of the .dome, when the shutters are in closed position.

A further object of the invention is to provide such a shutter construction in which cooperating baffles and drain troughs are provided at the outer edges of the shutters and the shutter, frames, for conducting and draining water outside of the dome.

A still further object of the invention is to providea construction in which the shutters are arcuately curved troughs are provided at the meeting edges of the shut- Likewise, it is an object ofthe invention to provide such a construction in which the frames for the shutters are also longitudinally curved and are provided with similarly curved baflies and drain troughs cooperating with longitudinally curved baflies and drain troughs through which water is drained to the exterior of the dome when the shutters are in closed position. H The above and other objects, apparent from the drawings and following description, may be attained, the above described difliculties overcomeandthe advantages .and results obtained, by the apparatus, construction, arrangement and combinations, subcombinations and parts which comprise the present invention, a preferred embodiment of which, illustrative of the best mode in which applicant has contemplated applying the principle, being set forthin detail in the following description and illustrated in the accompanying drawings.

In general terms, the invention may be briefly described as comprising a pair of sliding shutters for an observatory dome, the shutters being longitudinally curved to conform to the contour of the semi-spherical the shutters toward each other to close the opening when the telescope is not in use.

, Longitudinally curved bafiies and drain troughs are located at the meeting edges of the shutters and arranged to cooperate, when the shutters are in closed position, to form a tortuous path through which water entering the joint-between the shutters will be conducted and drained downward on the outside of the dome.

The outer edges of the shutters and the frames are provided with cooperating longitudinally curved bafiies and drain troughs which convey water downward outside of the dome when the shutters are in closed position. 7

Having thus briefly described the construction and operation of the invention, reference is now made'to the accompanyingdrawings showing a preferred embodiment of the invention, in which;

FIG. 1 is a perspective view of an observatory Wit dome equipped with shutters constructed in accordance with the invention, the shutters being shown in open po sition; i

FIG. 2 is a larger scale vertical sectional the dome, taken as on the line 2-2, FIG. 3; e FIG.- 3 is a vertical sectional view through the dome with the shutters in closed position, taken as on the line 3 i I:

FIG. 4 is a fragmentary plan sectional view of a por- ;tion of the dome, showing the shutters in open position; and

FIG. 5 is an enlarged, detached, plan sectional view of the shutters in closed position.

Referring now more particularly to the embodiment of the invention illustrated in the drawings, in which similar reference characters denote like parts throughout the several views, an observatory of substantially cylindric form is indicated generally at 10, capped by a semi-spherical dome indicated generally at 11. 7

As in usual practice, the dome 11 is mounted to revolve view through upon the observatory 10. Any suitable and well known resting thereon.

In order to hold the dome in alignment with the observatory as it revolves thereon, horizontal guide rollers 16 are journalled upon bearing brackets 17, mounted at spaced intervals upon the cap ring 14 of the observatory and have rolling contact with the depending annular channel member 18 attached to the inner perimeter of the base ring 15 of the dome.

The cylindric observatory 10 may be of any usual and well known construction, either masonry, concrete, strud tural steel or the like, and in itself forms no part of the present invention.

The semi-spherical dome 11 may be of any usual construction and comprises generally the arcuate steel ribs 19 connected at their lower ends to the base ring 15 and attached together at their upper ends at the top center of the dome, and covered with a sheet metal skin 20, which may be formed in segments as indicated in FIG. 1, and welded or otherwise attached to the ribs 19, at their edges.

An opening 21 is provided in one side of the dome 11, extending from the base ring 15 to a point beyond the top center of the dome, for the purpose of sighting a telescope therethrough when the shutters indicated generally at 22 and 22a are in open position as shown in FIGS. 1 and 4.

Longitudinally curved frame members 23 are mounted on the dome 11 at each side of the sight opening 21 therein. Each of these frame members is in the form of a flat plate of substantially arcuate shape conforming to the contour of the dome 11, and opposed arcuate channel members 24 and 25 are welded or otherwise attached to the exterior and interior edges respectively of the frame members, on the outer sides thereof. A longitudinally curved rib 26 is formed upon, or attached to the outer side of each frame member 23 at a point spaced from the exterior channel member 24 thereon.

The shutters indicated generally at 22 and 22a are longitudinally curved to conform to the contour of the semi-spherical dome 11, and are straight in cross section. 'Ihese two shutters are of generally similar construction, each comprising a spaced pair of longitudinally curved fabricated structural members with a longitudinally curved sheet metal skin welded or otherwise attached thereto.

These shutters are mounted for sliding movement toward and from each other so as to close or open the sight opening 21 in the dome. For this purpose a horizontal track rail 27 is located tangentially to the dome 11, spaced outwardly from the lower end of the sight opening 21 therein, and a similar track rail 27 is located above the dome 11, spaced rearwardly of the upper end of said sight opening.

The track rail 27 is mounted upon spaced bracket arms 28 secured to the base ring 15 of the dome adjacentto the lower ends of the frame members 23, and the track member 27' is mounted upon bracket arms 29 secured to upper ends of the frame members 23. Each of the track .rails 27 and 27 has a channel ball portion 30.

Rollers 31 and 31' are journalled upon the lower and upper ends respectively of the shutters 22 and 22a and ride upon the channel ball portion 30 of the track rails 27 and 27 so as to support the shutters entirely thereon. This permits the shutters to be easily and readily moved to open or closed position as desired.

The detail construction of the shutters is 'best shown in FIG. 5, and since there are some slight differences in the constructions of the two shutters, each will be described in detail. The shutter 22 comprises two spaced frame members indicated generally at 32 and 33. The shutter frame member 32 is located at'the meeting edge of the shutter 22, and the frame member '33 at the opposite edge thereof.

The shutter frame member 32 is formed of a flat metal plate 34 of arcuate shape to conform to the contour of the semi-spherical dome 11, and has the opposed, longitudinally curved channel members 35 and 36 welded or otherwise attached to the side thereof away from the shutter 22a, at the outer and inner edge-portions respectively of the plate 34. An outwardly open-longitudinally curved channel member 35 is welded to the outer side of the shutter 22 at the meeting edge thereof.

An outwardly open, longitudinally curved channel member 37 is welded or otherwise attached'to the opposite side of the arcuate plate 34 at apoint substantially midway between the inner and outer edges of said plate. These channel members form bafiies and drain troughs for any water or moisture which may enter between the shutters from the outside.

The shutter frame member 33 is formed of a flat plate .38 of arcuate shape to conform .to the contour of the dome 11, and has the opposed, longitudinally curved channel members 39 and 40 welded or otherwise attached to the side thereof toward the shutter frame member 32, at the outer and inner edge portions respectively of the plate 38.

A sheet metal skin 41 is welded or otherwise attached to the outer surface of the longitudinally curved channel members 35 and 39 of the shutter 22. Thus, the shutter frame members 32 and 3 3 and the sheet metal skin 41 form an integral shutter.

The shutter 22a is substantially similar to the shutter 22, although the positions of some of the elements thereof are reversed relative to similar elements in the shutter 22.

A frame member, indicated generally at 42, is provided at the meeting edge of the shutter 22. This frame member comprises a flat plate 43 of arcuate shape conforming to the contour of the dome 11, and provided at its outer and inner edge portions respectively, on the side toward the shutter 22, with longitudinally curved channel m b 44 and 4. respe ive y h ch a e Welded or otherwise secured thereto.

An angle member 46, which is longitudinally curved to co m t t ont ur o the shu e frame member is welded or otherwise attached to the outer side of said frame member at the meeting edge of the shutter 22a, and extends over the longitudinally curved channel member 35' upon the meeting edge of the shutter 22.

The shutter frame member indicated generally at 47 is located at the opposite edge of the shutter 22a from the frame member 42, and comprises a flat plate 48 of arcuate shape to conform to the contour of the dome. longitudinally curved channel members 49 and 50 are welded upon the side of the arcuate plate 48 toward the frame member 23, at the outer and inner edges respectively of the plate .48.

A sheet metal skin 51 is welded or otherwise attached at its edges to the shutter frame members 42 and 47, thus forming therewith the complete shutter 22a which is slidable toward and from the shutter 22.

For the purpose of protecting the channel track rails 27 and 27 from rain, snow and the like, when the shutters are in closed position, inverted channel-shape hoods 52 and 53 are attached to the lower and upper end portions respectively of the shutters 22 and 22a and adapted to overhang the outer .end portions of the track rails 27 and 27, respectively, when the doors are in closed position.

As best shown in FIG. 5, moisture entering between the meeting edges of the shutters 22 and 22a, in closed position, will be prevented from entering the interior of the dome or observatory. First, the angle member 46 .upon the shutter 22a, overhanging the channel drain trough 35' at the meeting edge of the shutter 22, will tend to prevent moisture from entering between the meeting edges of the closed shutters.

Any moisture passing between the angle member 46 and the channel drain trough 35' may be drained downward on the outside of the shutter 22 and discharged upon the exterior of the dome or observatory. Should any moisture pass down through the joint 54 between the meeting edges of the shutters 22 and 224, it will tend to be trapped in the drain trough 37 upon the frame 32 of the shutter 22 and pass downwardly therethrough and be discharged on the exterior of the dome or observatory.

Should the drain trough 37 be at any time filled with water, the water must pass through a tortuous path between the frame member 42 of the shutter 22a and the adjacent side of the drain trough 37 on the frame memmoisture which may enter between the ribs 26 of the frames 23 and the frame members 33 or 47 of the shutters 22 and 22a, respectively, will be drained downward and be discharged outside of the observatory through the drain troughs 24 of frames 23 or the drain troughs 40 and 50 upon the frame members 33 and 47 respectively of the shutters 22 and 220.

From the above it will be obvious that a completely water-tight shutter construction is provided for observatory domes so as to adequately protect telescopes and other costly equipment housed therein when the shutters are in closed position.

In the foregoing description, certain terms have been used for brevity, clearness and understanding, but no unnecessary limitations are to be implied therefrom beyond the requirements of the prior art, because such words are used for descriptive purposes herein and are intended to be broadly construed.

Moreover, the embodiments of the improved construction illustrated and described herein are by way of example, and the scope of the present invention is not limited to the exact details of construction.

Having now described the invention or discovery, the construction, the operation, and use of preferred embodiments thereof, and the advantageous new and useful results obtained thereby; the new and useful construction, and reasonable mechanical equivalents thereof obvious to those skilled in the art, are set forth in the appended claims.

I claim:

1. A water-tight shutter construction for a substantially semi-spherical observatory dome having a sight opening therein, said shutter construction comprising first and second longitudinally curved shutter members conforming to the contour of the dome, means mounting said shutter members for lateral movement toward and from each other in a common plane for covering and uncovering the sight opening in the dome, each shutter member comprising a laterally spaced pair of longitudinally curved shutter frame members and a longitudinally curved sheet member attached thereto at its lateral edges, a longitudinally curved outwardly open channel member connected to the shutter frame member at the meeting edge of the first shutter member on the side of said lastnamed shutter frame member toward the second shutter member and at a point intermediate the inner and outer edges of said last-named shutter frame member, a longitudinally curved outwardly open channel member connected to the inner edge of the shutter frame member at the meeting edge of the second shutter member and on the side thereof toward the first shutter member, and an outwardly disposed longitudinally curved angle member at the meeting edge of the second shutter member and overhanging the meeting edge of the first shutter member, a spaced pair of stationary longitudinally curved frame members mounted upon the dome at opposite sides of said sight opening, and opposed longitudinally curved channel members upon the surfaces of said stationary frame members and the corresponding shutter frame members at the far edges of said shutter members,

2. A water-tight shutter construction for a substantially semi-spherical observatory dome having a sight opening therein, said shutter construction comprising first and second longitudinally curved shutter members conforming to the contour of the dome, means mounting said shutter members for lateral movement toward and from each other in a common plane for covering and uncovering the sight opening in the dome, each shutter member comprising a laterally spaced pair of longitudinally curved shutter frame members and a longitudinally curved sheet member attached thereto at its lateral edges, a longitudinally curved outwardly open channel member connected to the shutter frame member at the meeting edge of the first shutter member on the side of said last-named shutter frame member toward thesecond shutter member and at a point intermediate the inner and outer edges of said last-named shutter frame member, a longitudinally curved outwardly open channel member connected to the inner edge of the shutter frame member at the meeting edge of the second shutter member and on the side thereof toward the first shutter memher, and an outwardly disposed longitudinally curved angle member at the meeting edge of the second shutter member and overhanging the meeting edge of the first shutter member, a spaced pair of stationary longitudinally curved frame members mounted upon the dome at opposite sides of said sight opening, opposed longitudinally curved channel members upon the surfaces of said stationary frame members and the corresponding shutter frame mebers at the far edges of said shutter members, and a longitudinally curved rib on the far side of each stationary frame member overhanging the adjacent channel member on the corresponding shutter frame member at the far edge of the corresponding shutter member when the shutter members are in closed position.

References Cited in the file of this patent UNITED STATES PATENTS 1,942,871 McDonald Jan. 9, 1934 2,488,257 Anderson Nov. 15, 1949 2,550,323 Bishop Apr. 24, 1951 FOREIGN PATENTS 205,778 Australia Dec. 15, 1955 OTHER REFERENCES Construction Methods Publication, October 1934, pages 38, and 39.

Palomar (text by Helen Wright), published by the Macmillan Co., NY. (1952), and 161. 

